Combustion of mixed gases.



W. A. BONE, W. WILSON 61 0. I McCOU RT.

COMBUSTION 0F MIXED GASES.

APPLICATION mzo ocns. I910. RENEWEI MAR. 11.1917.

1 22512 18. v Patented Apr. 17,1917.

WITNESSES Q: 3 W INVENTORS if s Warm/mm,

UNITED STATES P TENT OFFICE.

WILLIAM ARTHUR BONE, OF LEEDS,

GYIRIIL DOUGLAS MCCOURT, OF

JAMES WILLIAM WILSON OF ARMLEY, LEEDS, AND

LONDON, ENGLAND, ASSIG-JIORS -'1O RADIANT HEAT-- ING LIMITED, OF LONDON, ENGLAND, A CORPORATION OI? GREAT BRITAIN.

comnus'rrou or MIxnn'cAsns.

Application filed October 8, 1910, Serial No. 586,058.

To all whomz'tmay concern:

Be it known that we, WILLIAM An'rn'qn Bonn, residing at the University, Leeds, 1n the county of York, professor of appl ed 5 chemistry, Janus WILLIAM Wilson, residing at Carlton Works, Armley, Leeds, in the said county, gasstove manufacturer, and CYRIL Douoms' MCCOURT, residing at 13 Malwood road, Balham Hill, London, S. England, chemist, subjects of the King of Great Britain and Ireland, have made certain new and useful Inventions Relating to i the Combustion of Mixed Gases, of which the following is a specification, taken in connection with the accompanying drawing, which forms part of the same. Our invention relates to apparatus for burning a mixture of two or more gases or vapors which combine together to produce heat, hereinafter called the explosive mix- .t\.1re .(such for instance as a mixture of coal gas and air), the objects being to obtain complete combustion. and also to utilize as much as possibleof the heat for any desired purpose. The purposes to which our apparatus may be applied are numerous and include gas fires of various kinds.

In the accompanying drawing showing in. a somewhat diagrammatic way several illustrative embodiments of this invention, Figure 1 is a sectional View through one form of dia1'lhragm apparatusand Fig. 2 is a similar-view through a form of apparatus comprising a composite diaphragm.

In Fig. 1 of the accompanying drawing is represented a simple form of that which maybe described as the fundamental unit of our apparatus, which consists essentially of a permeable diaphragm A of suilicicntly re-- fractory material in conjunction with a chamber or .casing C The porous diaphragm constitutes one wall oi? the chamber, into which explosive mixture is led through a. pipe; The mixture passes through the diaphra'gm and is caused to ignite on the face of exit E or in close proximity thereto. For instance an explosive mixture of coal gas and air in proper proportions and at various Specification of Letters Patent.

lated so that lit le or no flame appears P atented Apr. 17, 1917.

Renewed March 1?, 1917. Serial No. 155,617.

pressures, exampl es of which are hereinafter given may be used for many household and industrial ymrpoees. The supply of gas and air in proper pi oportions may be suitably regulated by ordinary means, so that the combustion may sake place in, upon, or close to the surface F. of the porous diaphra A. The regulation of the supply oithemmture having been adjusted, the face E of the diaphragm A 101' comes hot or incandescent, and maintaim d in a heated or incandescent state by tlu. continlled flovy of the explosive mixture through the porous diaphragm, and its :ombustion in, upon, or near the surface of same. The flow can be re e.- yond the surface of the diaphragm while the B5 said surface is m aintained in a state of glow 6r incandescence.-

With regard ;o the combustible mixture the proportions 3f the combining gases will be sulnstantially the proportions. necessary "for complete co n'bustii'on. In general with coal gas, we prefer to employ a little excess oi air. For exal Iiple in the case of a'coal gas which theoretically requires about five and, a half times its own volume of air for corn- 7 5 plcte combustion, we have obtained good results with about seven times its own volume I of air. i

The joint bet ween the diaphragm A and its seatin S m: y be of white lead or an ashestos paste or other suitable luting mate rial, and a ring: ll may be used to secure the porous diaphragm in position. The margin of the diaphrag. n maybe glazed so as to prevent escape of g: sth rough its edges. The diaphragm may i): arranged in various ways depending on t 1e object in view. In Fig. 2' similar means a .e shown for mounting a die phrag'nn which in this easy: is of compositecharacter, the portion A being of different porosity from tl 1e layer A Forming the outer or working fact of the diaphragm. In some cases more thai one diaphragm may be employed. Whero plane diaphragms are employed they ma y be placed horizontally, ver- '95 tically or at my desired angland the heated external surt'aee may be either the superior or interior surf-are.

porous diaphragm of this general eharaeter may of eourse be formed with working fares of any desired shape. or contour. It should be noted however that where i there with any pa ltt'lllill n'lixt-ure of gases a tendeney to heat the diaphragm so mueh as to eause tiring bark. the arrangement must be sileh as to utilize or convey away the heat with sullieientrapidity to pre vent such tiring back.

IFor iustanee.-in using water-gas there is always a t'endeney to lirebaek. but this may be in a large measure ebunteraeted by employing diaphragms of a closer or less permeable texture so as to produee a steeper pressure gradient in the diaplu-agm, thereby increasing the eloeity oi. How of the explosive mixture through the diaphragm. i-\eeordingly it is desirable in any given ease to select from a series of dial'ihragms of different permeabilities that diaphragm whirh on trial is found to be suliieiently impervious to prevent tiring ark or back flashing under the given eonditions. Also the tendeney to'fire back maybe rhe'rked by mixing a larger proportion of inert gas or air with the explosive-mixture.' Further, where ing degrees of permeability or porosity there is risk of firing baek the progressive aeeumulation of heat in a eonfined space must be a\-oi ded.- ()n the other hand when using poor gases as for example blast furnace gas,-the production of the glow or ineandeseence depends on eonser ing'a. certain amount of the heat on the surtace ot the diaphragm.

It should be noted that in our RIPPHItlt-HS although the produets ofeombustion necessarilypass away in a heated eondition and thus earry ott' some of the heat generated, the arrangement. before deseribed enables. us when desired to reduee theeon eetire heat outflow and to utilize a large proportion of the heat in radiant form by radia- .tlon from the surface (it the heated dlaphragm, which for some applieations of our I invention is a matter of important-e.

The diaphragms or the like may be produeed from various materials either separately or in eombiuation. and may vary eonsiderably in their nature[- shai'iefand eonstruetion, examples of whieh .a re hereinafter specified. But it must be understood that wedo not. eonline.ourselves solely to the said exau'iples and that we may adopt other constructions .in the nature of a diaphragm or the like. so long as same enables us to burn a mixture of gases or the like and 'produee in. upon. or close to thesurfaee of the mediuur a combustion with little or no flame.

In the prod'uetion of the diaphragmssuitable refractory materials are employed and sueh diaphragms beingformed into one or superimposed. the more porous diaphragm being that which is on'the side of exit ofthe gaseous mixture.

The degree of porosity will be determined by the quantity of organic material em-.

ployed. in general we prefer to employ fine seed for this purpose as being a l'naterial the individual grains oi wlneh are substantially of the same size and. shape. \Ve hnd that rape seed is speeially suitable for this purpose. The proportions will vary son'ie\\-'l'1at with llle llalllllt' of the elay employed, some clays being by nature when burnt more porous than others. and inevery ease it is necessary to determine by trial the proper proportions for prmlueing a desiral degree of poi'osity. llut: the examples which we will give will serve to indicate in some measure the nature of the mixtures which are found suitable in praetiee.

In making diaphragms suitable /for work'- ing with eoalgas and air at. a pressure of six inches water gage, we mix 18 parts by weight of mwdered Stourljiridge fire-clay in the. dry state witlrS parts by weight of English rape-seed. and mix therewith sufiicient water to render the mixture suitable for mohling. :ltwill be found that the plasticity of the mixture. beeomes rapidly lost on standing owing to the dlinkin water by the. dry seed. Only su eient of the mixture should be made to suit immediate requirements. andthe diaphragms should be molded inunediately after the mixture is made and before it has lost its plasticity.

To obviate in part the loss of plasticity hereup of the in before mentioned the rape-seed. may be steeped in water prior to mixing with the clay. The molded diaphragms are carefully dried. baked and burned in an oxidizing atmosphere so as to' insure the complete burning out of the seed.

After burning. that surface of the diaphragm which is to form the heated surface is preferably roughened with a rasp Sand blast. or by any other known means. O r both surfaees of the diaphragmmay be so roughened.

By employing the above mentioned roportions we have made diaphra'gms w ich when three quarters of an inch thick are able at a pressure of six inches water. age to admit'of a flow per square incli'of eating surface of 6.4: c. ft. per hour of a gaseous mixture consisting of one volume of gas with 6 or 7 volumes of air.

By employing a mixture consisting of 18 ridge fire-clay with 12 parts by weight of English rape-seed we have made-diaphragms which when three quarters of an inch thick admit of the same gaseous flow at a pressure of one inehiwater'gage.

Another method of making porous diaphragms consists in consolidating amass of granules or fragments of refractory material in such a manner as to leave pores or interstices throughout the mass. For example burnt fire-clay coarsely ground and preferably meshed to a uniform size mixed with a powder adapted to act as a cementing material when highly heated may be disposed 'fr the form of diaphragmrequired, and

burned. Thus for working at a pressure of about one quarter of an inch water gage,

witha mixture of coal gas and air the grade of fragments employedis that whichpasses through asieve of eight meshes to the linear inch but will not pass a sieve of sixteen. meshes to the linear inch. These fragments are wetted, mixed with one-tenth of their weight of finely ground feldspar and molded or disposed into the form of diaphragm required, slight pressure only being used to give the diaphragm the desired form or configuration and burnt at a temperature of 1,300 or 1,-IlOO C. A series of such diaphragms made with diflering'degrees of fineness can-be used to, determine which is the 'best grade to use for any particular gaseous mixture. 7

-What we claim as our invention is 1. In apparatus forburning fuel, a porous composite diaphragm composed of porous non-metallic material and comprising a porous outer layer and a relatively denser inner portiommeans to feed an explosive mixture of gaseous or "aporous fuel and of supporter of combustion therefor through said diaphragm, said diaphragm being adapted when heated to cause the accelerated combustion of said explosive mixture to occur substantially without visible flame, within the porous outer layer of said diaphragm and maintain incandescence thereof, the in? candescent surface of said diaphragm being free to transmit by radiation heat supplied thereto from said combustion.

2: In apparatus for burning fuel, a thick porous composite refractory diaphragm comprising a porous outer layer and a relatively denser "inner portion, means to feed an explosive nixt'ure of gaseous fueland of supporter of combustion therefor through said diaphragm, said diaphragm being adapted parts by weight of dry powdered Stourwhen heated to cause the accelerated combustion of said explosive mixture to occur substantially wthout visible flame within said diaphragm and'maintai'n, incandescence thereof; 1

3. In apparai us for burning fuel, a" porous composite refractory diaphragm con-' sisting of non-metallic refractory material comprising a I)(I'011S outer layer and'a relatively denser inner portion, means to supply gaseous fuel ant means to supply air and to form an explosive mixture thereof and feed the same throng h said diaphragm, said diaphragm'being a lapted when heated to cause the accelerated. combustion of said mixture to occur substartially without visible flame within the outerlayer of-said'diaphragm and maintain :ncandescence ,of the outer surface thereof. a

4. In apparaiusfor burning fuel, a porous refractory diaphragm of non-metallic refractory mate rial, a casing within which said diaphragm is mounted, means to render the edge portions of said diaphragm substantially impe-vious'to gaseous material,

and means to fee (1 to said casing-and through said diaphragm an explosive gaseous mixture containing substantially the combining proportions of iir and of gas having high calorific value, 5 aid diaphragm being adapted when heated 10 cause the accelerated combustion of said explosive mixture to occur substantially w thout visible flame within the porous outer layer of said diaphragm and maintain i1 candescence thereof.

5. Apparatus for burning explosive gaseons mixtures, comprising aporous refractory diaphragm having a portion or layer adjacent its' on er or outlet side which is more porous than the inner portion of the diaphragm, and means for maintaining a supply of the e) plosive mixture against the inlet side of the diaphragm to cause the mixture to enter and move through the pas-' sages of the diaphragm to burn within the outer more por us layer thereof.

6. Apparatus for producing heat, co'mprising a porous refractory diaphragm having a portion or lay 2r adjacent its outer or outlet side which is more porous than the inner portion of the diaphragm, a gas chamher one wall of which is formed by the inner denser side f the diaphragm, and means for mixing a furl gas and air in proportions to form an explosive gaseous mixture and for supplying ,1 he explosive mixture thus formed to said chamber, whereby the mixture will be causi d to enter and move through the passages of the diaphragm to burn within the outer more porous layer thereof.

7. Apparatus for producing heat, comprising a porous refractory diaphra m, a gas chamber one will of which is ormed by said diaphragm, and means for mixing a fuel gas and air in proportions to form an In witness thereof, we have hereunto set 10 explosivegaseous mixture and for supplyour hands, in the presence of two witnesses.

ing the explosive mixture thus formed to VII LI KM :XRTHUP POYF said chamber, \vherehv the mixture. will be MfiF 'i A xvi caused to enter undhun'e through the pasb fil sages of the diaphragm to burn adjacent its outer face, the passages of the diaphragm be; \Vitnesses: mg of a SIM to prevent bael't-flaslnng of the \VM. Annie,

explosive mixture. C. TATTERSFIELD. 

